ECAT Pre General Science MCQ Test With Answer for Mathematics Chapter 9

Which one is not defined∀n∈Z+

• -n! A
• n! B
• (-n)! C
• n!+0!=n!+1 D

How many signals can be given by 5 flags of different colours, using 3 flags at a time

• 120 A
• 60 B
• 24 C
• 15 D

8 . 7 . 6. 5 in factorial form is

• 
  A
• 
  B
• 
  C
• 
  D

A committee consists of 9 experts taken from three institutions A, B, and C, of which 2 are from, A, 3 form B and 4 from C. If three experts resign, then the probability that they belong to different institutions is

• 1 / 729 A
• 1 / 24 B
• 1 / 21 C
• 2 / 7 D

• 
  A
• 
  B
• 
  C
• 
  D

• 3 A
• 6 B
• 0 C
• None of these D

n different objects can be arranged taken all at a time in ______

• (n + 1)! ways A
• (n - 1)! ways B
• n! ways C
• n ways D

• 56 A
• 7 B
• 8 C
• 8/7 D

A key ring is an example of

• Permutation A
• Circular permutation B
• Combination C
• None D

(n + 2) (n + 1) n= ______

• 
  A
• 
  B
• 
  C
• 
  D

When a selection of object is made without paying regard to the order of selection, it is called

• Sequence A
• Series B
• Combination C
• Permutation D

The sum of all odd numbers between 100 and 200 is

• 6200 A
• 7500 B
• 6500 C
• 3750 D

nCn-r is equal to

• n! A
• n-1Cr B
• nCr C
• None of these D

• 1.5 A
• 1.2 B
• 8 C
• None of these D

The number of permutations of n objects of which there are n₁like of one kind, n₂like of the second kind and n₃like objects of third kind are

• 
  A
• 
  B
• 
  C
• 
  D

Two coins are tossed twice each. The probability that the head appears on the first toss and the same forces appear in the two tosses is

• 1/4 A
• 1/2 B
• 1/3 C
• 1/7 D

There are 16 point in a plane, in which 6 are collinear. how many lines can be drawn by joining these points?

• 10 A
• 66 B
• 71 C
• 106 D

How many arrangements of the letters of the word MI SSI PPI, taken all together can be made?

• 
  A
• 
  B
• 
  C
• 
  D

• 8 A
• 1/56 B
• 56 C
• None of these D

Arithmetic mean between 14 and 18 is

• 16 A
• 17 B
• 15 C
• 32 D

Two unbiased dice are thrown. The probability that the total score is > 5 is

• 1 / 18 A
• 7 / 18 B
• 13 / 18 C
• 11 / 18 D

• 
  A
• 
  B
• 
  C
• 
  D

Number of ways of writing the letters of WORD taken all at a time is

• 24 A
• 4 B
• 12 C
• 6 D

If S is a sample space and event set E = S then P(E) is

• >0 A
• 1 B
• <1 C
• 0 D

• 
  A
• 
  B
• 
  C
• 
  D

In a country 55% of the male population has houses in cities while 30% have houses both in cities and in villages find the percentage of the population that has houses only in villages

• 45 A
• 30 B
• 25 C
• 50 D

• 0.9 A
• 0.74 B
• 0.2016 C
• None of these D

The sum if 1,3,5,7,9........ up to 20 terms is

• 400 A
• 472 B
• 563 C
• 264 D

If for two events A and B , P(A∪B)=1,then events A and B are

• Certain events A
• Mutually exclusive B
• Complementary events C
• Independent D

Number of permutations of n distinct objects taken r(<n - 3) at a time which exclude 3(<n) particular objects is

• 3! P(n, r - 3) A
• P(n, 3) P(n, r - 3) B
• P(r, r)P(n, r - 3) C
• P(n - 3, r) D